Evidence of large-scale amplitude modulation on the near-wall turbulence
Evidence of large-scale amplitude modulation on the near-wall turbulence
复制标题
近壁湍流大规模振幅调制的证据
DOI：
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发表时间：
2007
期刊：
影响因子：
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通讯作者：
I. Marusic
中科院分区：
文献类型：
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作者：
R. Mathis;N. Hutchins;I. Marusic
在壁面湍流中，大尺度运动和小尺度运动之间的关系仍然是一个知之甚少的过程。这种误解的部分原因可能是许多实验室规模设施的典型分离规模有限。 Hutchins 和 Marusic [11] 最近在高雷诺数湍流边界层中进行的一项研究定性地表明了大尺度对数区域运动对小尺度近壁循环的调节影响的存在。在本研究中，我们以这些观察为基础，使用希尔伯特变换应用于脉动速度信号的光谱过滤小尺度分量，以便定量确定大尺度结构对近壁循环施加的幅度调制程度。
The relationship between large- and small-scale motions remains a poorly understood process in wall-bounded turbulence. Such misunderstanding is perhaps, in part, due to the limited scale separation typical of many laboratory-scale facilities. A recent investigation performed by Hutchins and Marusic [11] in a high Reynolds number turbulent boundary layer has qualitatively shown the existence of a modulating influence of the large-scale log region motions on the small-scale near-wall cycle. For this study we build upon these observations, using the Hilbert transformation applied to the spectrally filtered smallscale component of fluctuating velocity signals, in order to quantitatively determine the degree of amplitude modulation imparted by the large-scale structures onto the near-wall cycle.